1984 Mercedes 380SL RestoMod

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Built most of the IRS on the bench

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I sent my stock radiator off to Ron Davis Radiators and he sent this beautiful radiator back. Rubber mounts fit perfect on the sides. Fits perfect! Two huge Spal fans. I have been using Ron Davis radiators for years in all the swaps I do. In a Land Cruiser the fans turn off at 35MPH and keep temps down without issue.

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All of the IRS components have been media blasted and shot with epoxy primer

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I bought this to do something similar, but more budget friendly. I'm doing a 5.3 ls with GTO oil pan and leaving the mercedes suspensions in place. Red car is not mine, but has gto oil pan. I'm told it will fit as is.

Im not a fan of the r107 rear diff ratio( 2.67:1?). I'm hoping the truck cam can make enough torque to pull those gears. If not, I will swap in some other axle with better gears and do a cam swap.

Like you, I'm ditching the problematic parts and street rodding the car (wire harness, gauges, and air conditioning).

Wheels are 17" AMG wheels.

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Rear diff is one of the components that turned me away from the LS swap, (or a turbo). I don't think the half shafts are up to the torque. The m117 is smooth, but really hard to get much better than 8.5:1 compression. Theres just no aftermarket. Also, the 722.0 trans isn't up to big power. I think it's rated to 362 ft-lbs. I would think a 4L60 or 6L65 would require some floor mods, but tunnel mods need to stop before the seat rails

It really helps to have somebody who has worked through all the problems, and I couldn't find much info out there. If you found a source, it'd be a big help.

I have used the gto pan on several swaps it inexpensive and it fits nice. There are pans that go further. I have a Devious Customs on my Linc, and there is another similar pan available.

 
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Rear diff is one of the components that turned me away from the LS swap, (or a turbo). I don't think the half shafts are up to the torque. The m117 is smooth, but really hard to get much better than 8.5:1 compression. Theres just no aftermarket. Also, the 722.0 trans isn't up to big power. I think it's rated to 362 ft-lbs. I would think a 4L60 or 6L65 would require some floor mods, but tunnel mods need to stop before the seat rails

It really helps to have somebody who has worked through all the problems, and I couldn't find much info out there. If you found a source, it'd be a big help.

I have used the gto pan on several swaps it inexpensive and it fits nice. There are pans that go further. I have a Devious Customs on my Linc, and there is another similar pan available.


Hopefully a 285 hp 5.3 will be a performance gain, but not too much that it breaks parts. Yeah the trans tunnel will need some love. I have to finish my current truck project before I tear into the mercedes. This thread gets me fired up. I like the plan for the rear wheel openings. I looks more muscle car-ish.
 
I bought this to do something similar, but more budget friendly. I'm doing a 5.3 ls with GTO oil pan and leaving the mercedes suspensions in place. Red car is not mine, but has gto oil pan. I'm told it will fit as is.

Im not a fan of the r107 rear diff ratio( 2.67:1?). I'm hoping the truck cam can make enough torque to pull those gears. If not, I will swap in some other axle with better gears and do a cam swap.

Like you, I'm ditching the problematic parts and street rodding the car (wire harness, gauges, and air conditioning).

Wheels are 17" AMG wheels.

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I am interested to see what you do with yours. You may just get away with the gears with the truck cam. I have concerns over trying to put bigger HP and TQ number motors in while retaining the rear diff and half shafts. I also do not like the excessive camber when the car is lowered. That is what drove me to going all out and install all new suspension. Better handling does not hurt either (at least that is the goal). I am liking the long tube headers on the red car, low hanging fruit when the car is lowered though. Mine sits with the rocker pinch welds 4.75" above the frame table now.
 
I like the plan for the rear wheel openings. I looks more muscle car-ish.
I thought the very same thing. I'll probably tackle that job after I get the motor and trans situated. I have a bit of tunnel work to do to raise the drive shaft and will not know about trans fit until it's here, looks encouraging. Also a good bit of metal to replace around the IRS. So i figure I'll do the wheel wells when I do all the other metal work. Still batting around the rear deck spoiler in my head as well.
 
I thought the very same thing. I'll probably tackle that job after I get the motor and trans situated. I have a bit of tunnel work to do to raise the drive shaft and will not know about trans fit until it's here, looks encouraging. Also a good bit of metal to replace around the IRS. So i figure I'll do the wheel wells when I do all the other metal work. Still batting around the rear deck spoiler in my head as well.
I've seen a couple with raised rear openings, but they also ran flares. I don't need flares with my wheel choice though. Your tape mockup appealed to me with the idea of imitating the front arches.
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I plan on tucking the US bumpers and making new side pieces out of steel and reworking the front valance. Fog lights and turn signals are going away. Bumpers will be painted body color along the lines of this red car (mercedes design study?). Rear arches may be raised on it. I plan on keeping us headlights. I plan on dual exhaust with dual exhaust tips in each corner.
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Im also considering turning my intake around and using the cowl plenum as cowl induction for the engine. I plan on reworking the firewall/inner fenders for looks too. I'm starting with a $1,000 car,I might as well have fun with it.
 
I'd not thought of turning the intake around and using the cowl. I am assuming you are speaking of the spot where the fans are mounted for the HVAC. I like the black trim as well. I plan on using European bumpers with US headlights. I also am planning on fire wall and inner fender work. I am up to my ears in customer jobs right now and have not touched the car in a couple weeks. I still have a bit of metal removal to do prior to Welding the IRS in place.
 
I'd not thought of turning the intake around and using the cowl. I am assuming you are speaking of the spot where the fans are mounted for the HVAC.
Yeah that is where I want to hide my air cleaner. I want to eliminate the fan holes and pull intake air through the cowl vents.
 
I like that idea.
 
Finished the cut outs for upper arm clearance. The cut outs will be boxed in and reinforced over the top.

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Spent some time cutting the trunk floor out and cleaning things up a bit.

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I like that idea.
Feel free to try it.
Spent some time cutting the trunk floor out and cleaning things up a bit.

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Since the rear axle is going to be where the gas tank was, are you putting a gas tank where the trunk floor was?

Any thought on modifying the rear valence to be lower? (So you could hide mufflers and an under the floor gas tank).

Not this exactly, but the same idea. ....drop down deeper behind the rear wheels and have a deeper roll pan under the bumper (no upside down spoiler though, just a roll pan)
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Plan is to mount a tank where the spare used to be.
I've thought about the area under the rear bumper. rather empty under there. That is the extent of it though. I am concentrating on suspension then drive train.
 
Setting up the rear chunk on the Mercedes to check out mounting points for the upper support bar.

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I got the C channels welded in on both sides. There will be a cross member bolted into welded in mounts that are welded to the Hoz section of the C channel. Another 2x3 x 1/8" box cross member between the original frame rails just in front of the notch for the sway bar. Angle braces coming off the roll bar will tie in at that cross member.
Humidity never went below 85% today, again. Everything is flash rusting over night. I got sick of wire wheeling rust every time I want to do some work so I primed everything again.

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We've got power!! I made some progress on Babs yesterday. The IRS is sitting where it lives with everything at ride height. Its going to need some cutting to clear the coil overs. You can eyeball the plumb line through the hubs and the diff (red dot is the blast cabinet on the other side) and line them up and also with a center line marked on the diff housing. Same from both sides. Working on the mounts tomorrow if time allows.

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Upper and forward cross members in place, still a good bit of welding and bracing left to do but it is where it lives. There are two more braces that attach to the lower arms forward to a point under the car. This is an issue with no easy solution. Cant wait to figure out sheet metal.......................

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